Centrifugal fan.



l PATENTE@ DEG. 1v, mov; GOUSANS. IPUGAL FAN" No. 373,923. v L. B'.

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No. 73y923. PATENTES) DEU. l?, 1907,

L.l B. Gowns. GENT-RIFUGAL FAN. APPLI-CAION FILED EAN13, 1907.

No. 873,923. PATENT@ DEG. 17, 1907.

- L. B. GOUSANS. @Mmmm-.L FAN.

APPLOATIUHK'EILED MAR, 13, 1907. v

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LGUI .BERTRAM GOUSANS, OF LINCOLN, ENGLAND.

CENTRIFUGAL FAN.

- Specication of Letters Eatent.

Patented Dec. 17, 1907.

Application tiled m9101113. 1907. Serial No. 362232.

To all whom 'it may concern.- l

its it known that l, LOUIS BERTRAM Conserve, ci 7 outh Park, in the city and county of Lincoln., England, engineer, have invented certain new and useful Improve ments in or Relatingto Centrifugal Fans, of which the following is a speciication- This invention relates to fans and has for its objectI to eliminate, irrespective of the speed ci rotation, the hum, note or shriek hich accompanies the working of ordinary cased fans.

l believe that the above mentioned phenomena are almost entirely due to the fluid impulses created by the venes, which occur in rapid and periodic succession, comin into direct contact or communication, radiayly or tangentially with the case of the fan: l rind that the before mentioned phenomena is prevented it ineens are interposed between the periphery oli the ian and the casing for preventing tl A ing to the easing, and according to this invention l apply around the ian wheel a circuniferentially fitted screen, shroud or' other device adaptedv for interrupting the fluid impulses and l practically preventing them reaching the casing, the said device or shroud is hereinafter referred 'to as the shroud or Huid impulse interruptor and it may be of plain7 corrugated or perforated niet .l oiv wire, wire work or wire gauze or ier suitable construction. The said shroud is preferably arranged concentric .spindle and it may be iixed to or a part of either the fan or the seine iorins it may be described e easing in which iorn'l the A trtially as a` dellector to .cidentally serves to maintain frein the discharge. -tion is ap licable to any type oi ientriiugai ty e and the invenw cally applicab c to exhaust and S. tion is advantageously ein loyed ui with fans the production of a note by obiectionahle.

oanymg drawings show the in and similar letters refer to il and 2. respectively longitu ie saidluid impulses i'roin pass" -between the shroud and the In Figs. 3 and 4 afan Wheel of the known' for organ lo owingv several. Ways to teils oi.

dinal and transverse sections of a fan blower suitable for organ blowingpurposes and having the invention applied thereto. Figs. 3 and 4 are respectively longitudinal and transverse sections of a fan of the Sturte- `vant type having the invention applied thereto.

Figs. 5 to 15 are cross sectional views of' the peri )heral parts of different varieties of an's showing different Ways of applying the invention thereto. Fig. 16 is a sectional side elevation of Fig. 14. A

In Figs. 1 and 2. c is the fan wheel of the double inlet type inclosed in a square casing c7 the fan bladesA are mounted on each side of a central disk o. d'A d are the `air inlets apertures and e is the discharge. 7i is the shroud which forms the subject of the present invention; in. this construction the said shroud rotates with the ian Wheel a and is of plain sheet instal fixed to the central disk c and projects therefrom over both sidesof the fan, being of about the saine `width as the fan blades but of less width than the casing s0 as to leave rooin at the sides of the casing for the passage of the air to the space i casing.

type is .inclosed in a snail shaped casing which is sufficiently enlarged if required to accommodate the shroudI #which is suitably spaced from the periphery of the fan Wheel a, the said shroud 1s here fixed to the central disk j of the fan Wheel and.. in Width the shroud is slightly largerthan the periphery of the wheel but as before'mentioned of less Width than the casingfc.v f Referring now tothe several varieties of shrouds illustrated. sonie are shown solid'and othersperforated or made of gauze but they niay be all more or less perforated or all solid.

.ln Fig.I 5 o is the izan Wheel, c the Casin and it the shroud, inthis case attached to the periphery of the ian casing as at c and made of Wire gauze.-

'l'n Fig. 6 theshroud /i is attached to an eX- tension l' oi" the side f" Wheel blades o', are mounted and the said shroud la extends from the disk lc over the fan Wheel blades, the opening between the shroud and casing being on one side only.

Fig. 7 shows a narrower conoidal type of tan wheel c and shroud h also narrow andl attachedto the fan Wheel by straps'or bracltets it.

eislr upon .which the ian Fig. 8 shows a similar construction to Fig. 6 where the disk on which the fan wheel blades are mounted is extended in a curve over the tips of the blades to form the shroud h.

Fig. 9 shows a similar construction to rig;

"6 where one of the side plates m of a conoidal Fig'. 13 shows a il-shaped shroud 7L attached directly upon the periphery of the fan wheel a.

Fig. 14 shows a shroud it fitted to a fan whee a which has a casing of circular cross section around the periphery of the fan, the shroud being fixed to the casing and ol' perforated material. l

Figs. 15 and 16 showa construction where the blades of the fan wheel a are extended outward and circumlerentially in a curve so as to overlap, as at o and forni the shroud lt; the overlapping parts being suitably secured and the side plates of the fan or the contour of the casing is so arranged that the air is discharged from the fan laterally as shown by the arrows at p. In connection with this last mentioned construction the fan' wheel may be said to be closed on its periphery andl sides with the exception of the axial intake and the lateral slots or openings close to the periphery by which the air passes into the casing.

W hat l claim and desire to secure by Letters Patent is 1. rlhe combination of a centrifugal fan wheel and casing therefor, a continuous shroud of not less tnan half the width of the blades and not greater width than the blades, said shroud being disposed around the periphery of the fan wheel blades and spaced apart therefrom. so as to leave an annular space between the shroud and the tips of the fan. wheel blades, said annular space being laterally open'to the casing.

2. The combination of a centrifugal fan wheel and casing therefor, and. a continuous shroud disposed around the fan wheel at a short. distance from the tips of the ian wheel blades, so as to leave an annular space o ening laterally into the casing, said shrou( being ol a width not loss than half the width of the blades for the purpose of obtaining the silencing client.

3. The combination of a centrifugal fan wheel and casing therefor, a continuous but perforated shroud of not less than half the width of the blades and not greater width than the blades, said shroud being disposed around the periphery of the 'fan wheel blades and spaced apart therefrom so as to leave an annular space between the shroud and the tips of the fan wheel blades, said annular space being laterally open to the casing.

4. In an incased ientrifugal fan, a continue ous but perforated shroud disposed around the fan wheel at a short distance from the tips of the fan wheel blades, so as to leave an annular space opening laterally into the casing, said shroud being of a width not less than half the width of the blades for the purpose of obtaining the silencing effect and lnot greater than the width of the blades to avoid detrimental back pressure in the discharge oi air from the fan wheel, substantially as set forth.

5. The combination of a fan casing, a shaft, a hub thereon, a disk on said shaft, fan vanes on said disk, an extension of said disk 1nd a continuous shroud mounted upon said bxtension oi the disk and disposed circumlfi-rentially around the fan wheel between the easing ,and the tips of the blades, said oo ntinuous shroud being of a width not less than haltl the width ol' the fan blades for the purpose of obtaining the silencing eilect and not greater than the width of the blades to avoid detrimental back pressure on the discharge of air from the fan wheel, substantially as set forth.

6. The combination oit a centrifugal fan wheel and casing therefor, a continuous wire gauze shroud of not less than halt` the width' of the blade ar'l not greater width than the blades, said shroud being disposed around the periphery of the ran wheel blades and spaced apart therefrom so as to leave an annular s ace between the shroud and the tips of the an wheel blades, said annular space being laterally open to the casing.

7. The combination of a centrifugalfan wheel and casing therefor, the fan wheel comprising blades adapted to whirl the air at least at ap roximately the velocity oi the tips of the blades, and an interruptor intern osed between the casing and the tips of the )lades to preventvtho fluid impulses from 'passing from the blades to the easing.

8. The combination of a centrifugal lan' Wheel and casing therefor, the fan wheel cornprising approximately radial blades adapted to whirl the air at least at approximately the velocity of the tips oi the blades, and an interrupter interposed between the casing and the tips of the blades, the space between the interru )ter and the blades being open laterally.

n witness whereof, l have hereunto signed my name in the presence of two subscribing witnesses.

LOU IS B [C lt'l HAM COI irlA NS..

Vi t1 losses Trios, Il. (look, lloaAcn Bonn. 

